Golf club head with improved inertia performance

ABSTRACT

A golf club head that is capable improving on the inertia properties of a golf club head all while also improving the Center of Gravity (CG) location is disclosed herein. More specifically, the golf club head in accordance with the present invention achieves a relative low Moment of Inertia (MOI) about the Z-axis (MOI-Z) as well as a relatively low MOI about the Shaft-axis (MOI-SA), all combined with a high MOI about the X and Y-axis (MOI-X and MOI-Y) and maintaining a consistently and relatively low CG location measured along a direction tangent to the hosel axis along the X-Y plane (CG-B).

RELATED APPLICATIONS

The present application is a continuation-in-part of co-pending U.S.application Ser. No. 16/539,622, filed on Aug. 13, 2019, which is acontinuation-in-part of co-pending U.S. application Ser. No. 16/219,651,filed on Dec. 13, 2018, the entirety of which are incorporated byreference herein.

FIELD OF THE INVENTION

The present invention relates generally to a new and improved golf clubhaving improved Moment of Inertia (MOI) characteristics, combined withan improved Center of Gravity (CG) location. More specifically, the golfclub head in accordance with the present invention achieves a relativelow Moment of Inertia (MOI) about the Z-axis (MOI-Z), a low MOI aboutthe Shaft Axis (MOI-SA), all combined with a high MOI about the X andY-axis (MOI-X and MOI-Y) and maintaining a consistently and relativelylow CG location measured along a direction normal to the hosel axisalong the X-Y plane (CG-B).

BACKGROUND OF THE INVENTION

With the development of the modern day oversized metalwoods, theperformance capabilities of these types of golf clubs have increaseddramatically over their predecessor, “the persimmon wood”. One of theways these metalwood type golf clubs have been performing better thantheir predecessors is in the increase in overall distance, generallyattributed to the inherent elastic deformation of thin metallic metalmaterials used by these metalwoods. Another way the metalwood type golfclubs have been outperforming their predecessors is in the increase inoverall forgiveness of the golf club head, generally attributed to theincrease in the MOI of the golf club head itself.

The MOI of a golf club head generally is a term used to describe theability of an object to resist rotational movement upon impact with asecondary object. In the case of a golf club head, MOI refers to theability of the golf club head to resist undesirable twisting upon impactwith a golf ball, as such a twisting movement will generally change theface angle of the golf club head away from the intended target line,sending the golf ball away from the intended target.

U.S. Pat. No. 5,354,055 to MacKeil shows one of the earliest attempts toincrease the MOI of a golf club head by placing the Center of Gravity(CG) location rearward. U.S. Pat. No. 6,364,788 to Helmstetter et al.shows the utilization of weighting members to help control the MOI ofthe golf club head. Both of these patents refer to the MOI-y of the golfclub head, as it relates to the ability of the golf club head to staystable when encountering an off-center impact in the heel and toedirection.

U.S. Pat. No. 7,850,542 to Cackett et al. illustrates a furtherdevelopment in the MOI research wherein a recognition of the differentaxis of rotation of the different MOI's. (Alternatively known as Ixx,Iyy, and Izz instead of MOI-X, MOI-Y, and MOI-Z) Despite the recognitionand identification of the difference in MOI values, U.S. Pat. No.7,850,542 only focuses its attention on Ixx and Iyy (adapted and changesto the current reference nomenclature), without any recognition of theimportance of the last MOI number, Izz, nor MOI-SA and how they canaffect the performance of the golf club.

Despite the above, none of the references recognizes the importance ofthe MOI of the golf club head horizontally forward and aft of the face(MOI-Z), and ways to design a golf club that takes advantage of theperformance characteristics of golf club with more optimal MOI-Z valuesalong with the minimized MOI-Sa values. Moreover, a closer investigationof the MOI-Z values will yield CG locations that will work inconjunction with the above MOI-Z values to create more performance.Hence, it can be seen from the above there is a need for more researchand a design of a golf club capable of achieving better performance byinvestigating the importance of MOI-Z and MOI-SA as well as the CGlocation and designing a golf club head.

BRIEF SUMMARY OF THE INVENTION

One aspect of the present invention is a golf club comprised of a golfclub head, a shaft coupled to the golf club head at a first end of theshaft and a grip coupled to the shaft at a second end of the shaft,where the golf club head comprises of a frontal portion furthercomprising a striking face that defines a face center, located at aforward portion of the golf club head; a rear portion located aft of thestriking face; and at least one weighting member located near a centralportion of the golf club head in a heel to toe orientation,substantially in line with and behind the face center; wherein an x-axisis defined as a horizontal axis tangent to a geometric center of saidstriking face with the positive direction towards a heel of said golfclub head, a y-axis is a vertical axis orthogonal to said x-axis with apositive direction towards a crown of said golf club head, and a z-axisbeing orthogonal to both said x-axis and said y-axis with a positivedirection towards a frontal portion of said golf club head, and whereinsaid golf club head has a MOI-Y to MOI-Z ratio of greater than about1.50.

In another aspect of the present invention is a golf club headcomprising of a golf club head comprising of a frontal portion furthercomprising a striking face that defines a face center, located at aforward portion of the golf club head, a rear portion located aft of thestriking face, and at least one weighting member located near a centralportion of the golf club head in a heel to toe orientation,substantially in line with and behind the face center; wherein an x-axisis defined as a horizontal axis tangent to a geometric center of saidstriking face with the positive direction towards a heel of said golfclub head, a y-axis is a vertical axis orthogonal to said x-axis with apositive direction towards a crown of said golf club head, and a z-axisbeing orthogonal to both said x-axis and said y-axis with a positivedirection towards a frontal portion of said golf club head, and whereinsaid golf club head has a MOI-X, MOI-Z, and CG-Z numbers that satisfiesthe equation

$\frac{{MOI} - X}{{MOI} - Z} \geq {\left( {{{6.7}501*CG} - Z} \right) - {9{9.3}{0.}}}$

Another aspect of the present invention is a golf club head comprising astriking face, a crown return, a sole return and a central body memberthat are formed of metal. The central body member is located near thecentral portion of said golf club head in a heel to toe orientation,substantially in line along the z-axis, and extends from the crownreturn and the sole return to a back edge of said golf club.

Preferably, the golf club head is further comprised of a heel bodymember made of a non-metallic material and coupled to a heel side of thecentral body member and a toe body member made of a non-metallicmaterial and coupled to a toe side of the central body member. The golfclub head can further include two weight members, one forward near thestriking face and one aft near the back edge. In one embodiment, a wallmember is coupled to a crown portion of the central body member and asole portion of the central body member and extends between the firstand second weight members.

In another embodiment, the golf club head is further comprised of acentral support member that is comprised of a plurality of angled strutmembers extending form the crown to the sole between the two weightmembers. Preferably, a first angled strut member extends from a crownportion of the central body member to the sole and a second angled strutmember extends from a sole portion of the central body member to thecrown, and the first and second angled strut members cross each other.More preferably, the first and second angled strut members extend at anangle of between 15 degrees and 75 degrees from both the y-axis and thez-axis. The golf club head can further comprise a third angled strutmember that extends from a crown portion of the central body member tothe sole and a fourth angled strut member that extends from a soleportion of the central body member to the crown, and the third andfourth angled strut members cross each other. The third and fourthangled strut members also extend at an angle of between 15 degrees and75 degrees from both the y-axis and the z-axis, and preferably, thethird angled strut member is coupled to the first angled strut memberand the fourth angled strut member is coupled to the second angled strutmember. The golf club can further comprise a vertical strut memberextending vertically, substantially parallel to the y-axis, between thefourth angled strut member and the third angled strut member.

These and other features, aspects and advantages of the presentinvention will become better understood with reference to the followingdrawings, description and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features and advantages of the invention will beapparent from the following description of the invention as illustratedin the accompanying drawings. The accompanying drawings, which areincorporated herein and form a part of the specification, further serveto explain the principles of the invention and to enable a personskilled in the pertinent art to make and use the invention.

FIG. 1 of the accompanying drawings shows a perspective view of a golfclub head in accordance with an exemplary embodiment of the presentinvention;

FIG. 2 of the accompanying drawings shows a top view of a golf club headin accordance with an exemplary embodiment of the present invention;

FIG. 3 of the accompanying drawings shows a frontal view of a golf clubhead in accordance with an exemplary embodiment of the presentinvention;

FIG. 4 of the accompanying drawings shows a plot of MOI-Z vs MOI-Ynumbers for the current invention, compared to prior art golf clubheads;

FIG. 5 of the accompanying drawings shows a plot of MOI-Z vs MOI-ShaftAxis numbers for the current invention, compared to prior art golf clubheads;

FIG. 6 of the accompanying drawings shows a plot of MOI-Y vs MOI-ShaftAxis numbers for the current invention, compared to prior art golf clubheads;

FIG. 7 of the accompanying drawings shows a plot of MOI-X vs MOI-ShaftAxis numbers for the current invention, compared to prior art golf clubheads;

FIG. 8 of the accompanying drawings shows a plot of MOI-Z vs CG-B/FaceWidth numbers for the current invention, compared to prior art golf clubheads;

FIG. 9 of the accompanying drawings shows a plot of MOI-Z vs CG-B/HeadWidth numbers for the current invention, compared to prior art golf clubheads;

FIG. 10 of the accompanying drawings shows a plot of MOI-X/MOI-Z vs CG-Znumbers for the current invention, compared to prior art golf clubheads;

FIG. 11 of the accompanying drawings shows a plot of MOI-Y/MOI-Z vs CG-Znumbers for the current invention, compared to prior art golf clubheads;

FIG. 12 of the accompanying drawings shows a plot of (MOI-X+MOI-Y)/MOI-Zvs CG-Z numbers for the current invention, compared to prior art golfclub heads;

FIG. 13 of the accompanying drawings shows an exploded sole perspectiveview of a golf club head in accordance with an exemplary embodiment ofthe present invention;

FIG. 14 of the accompanying drawings shows a horizontal cross-sectionalview of a golf club head in accordance with an exemplary embodiment ofthe present invention;

FIG. 15 of the accompanying drawings shows a vertical cross-sectionalview of a golf club head in accordance with an exemplary embodiment ofthe present invention;

FIG. 16 of the accompany drawings shows a perspective view of a golfclub head in accordance with an alternative embodiment of the presentinvention;

FIG. 17 of the accompanying drawings shows a top view of a golf clubhead in accordance with an alternative embodiment of the presentinvention;

FIG. 18 of the accompanying drawings shows a frontal view of a golf clubhead in accordance with an alternative embodiment of the presentinvention;

FIG. 19 of the accompanying drawings shows a horizontal cross-sectionalview of a golf club head in accordance with an alternative embodiment ofthe present invention;

FIG. 20 of the accompanying drawings shows a vertical cross-sectionalview of a golf club head in accordance with an alternative embodiment ofthe present invention;

FIG. 21 of the accompanying drawings shows a top view of a golf clubhead in accordance with an alternative embodiment of the presentinvention;

FIG. 22 of the accompanying drawings shows a frontal view of a golf clubhead in accordance with an alternative embodiment of the presentinvention;

FIG. 23 of the accompanying drawings shows a top view of a body portionof the golf club head in accordance with an alternative embodiment ofthe present invention shown in FIG. 21;

FIG. 24 of the accompanying drawings shows a bottom view of a bodyportion of the golf club head in accordance with an alternativeembodiment of the present invention shown in FIG. 21;

FIG. 25 of the accompanying drawings shows a vertical side view of abody portion of a golf club head in accordance with an alternativeembodiment of the present invention;

FIG. 26 of the accompanying drawings shows a vertical side view of abody portion of a golf club head in accordance with an alternativeembodiment of the present invention;

FIG. 27 of the accompanying drawings shows a top view of a golf clubhead in accordance with an alternative embodiment of the presentinvention;

FIG. 28 of the accompanying drawings shows a top view of a body portionof the golf club head in accordance with an alternative embodiment ofthe present invention shown in FIG. 27;

FIG. 29 of the accompanying drawings shows a bottom view of a bodyportion of the golf club head in accordance with an alternativeembodiment of the present invention shown in FIG. 27;

FIG. 30 of the accompanying drawings shows a top view of a body portionof the golf club head in accordance with an alternative embodiment ofthe present invention shown in FIG. 27;

FIG. 31 of the accompanying drawings shows a bottom view of a bodyportion of the golf club head in accordance with an alternativeembodiment of the present invention;

FIG. 32 of the accompanying drawings shows a cross-sectional view of afirst weight member shown in FIG. 31;

FIG. 33 of the accompanying drawings shows a cross-sectional view of asecond weight member shown in FIG. 31;

FIG. 34 of the accompanying drawings shows a bottom perspective view ofanother embodiment of a golf club head in accordance with the presentinvention;

FIG. 35 of the accompanying drawings shows a cross-sectional view of thegolf club head in accordance with an alternative embodiment of thepresent invention shown in FIG. 34;

FIG. 36 of the accompanying drawings shows a close-up, cross-sectionalview of the golf club head in accordance with an alternative embodimentof the present invention shown in FIG. 34;

FIG. 37 of the accompanying drawings shows a close-up, cross-sectionalview of the golf club head in accordance with an alternative embodimentof the present invention shown in FIG. 34;

FIG. 38 of the accompanying drawings shows a bottom perspective view ofanother embodiment of a golf club head rear portion in accordance withthe present invention;

FIG. 39 of the accompanying drawings shows a frontal view of the golfclub head rear portion in accordance with an alternative embodiment ofthe present invention shown in FIG. 38;

FIG. 40 of the accompanying drawings shows a close-up, cross-sectionalview of the golf club head in accordance with an alternative embodimentof the present invention shown in FIG. 38; and

FIG. 41 of the accompanying drawings shows a close-up, cross-sectionalview of the golf club head in accordance with an alternative embodimentof the present invention shown in FIG. 38.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description describes the best currentlycontemplated modes of carrying out the invention. The description is notto be taken in a limiting sense, but is made merely for the purpose ofillustrating the general principles of the invention, since the scope ofthe invention is best defined by the appended claims.

Various inventive features are described below and each can be usedindependently of one another or in combination with other features.However, any single inventive feature may not address any or all of theproblems discussed above or may only address one of the problemsdiscussed above. Further, one or more of the problems discussed abovemay not be fully addressed by any of the features described below.

Before beginning the discussion on the current inventive golf club headand its performance criteria, it is worthwhile to note here that thediscussion below will be based on a coordinate system 101 and axis ofmeasurement that is critical to the proper valuation of the performancenumbers. Hence, it is important to recognize here that although thespecific names given for the measurements below are important to theunderstanding of the current invention, the naming nomenclature shouldnot be viewed in vacuum. Rather, the importance is the numbers presentedbelow needs to be taken in context with how the coordinate systemrelates to the golf club head itself. In order to provide sufficientinformation to avoid any ambiguity, each of the figures provided belowreferencing a golf club head will all be accompanied by a coordinatesystem that is all consistent with one another.

Pursuant to the above, and to establish the reference coordinate systemfor the subsequent discussion, FIG. 1 of the accompanying drawings showsthe coordinate system 101 that will be used to define the variousmeasurement and performance figures for the current invention. Thex-axis used by the current discussion refers to the axis that ishorizontal to the striking face from a heel to toe direction. The y-axisused by the current discussion refers to the vertical axis through theclub in a crown to sole direction. The z-axis used by the currentdiscussion refers to the horizontal axis that is horizontal front toback in a forward and rear direction. Alternatively speaking, it can bethe x-axis is defined as a horizontal axis tangent to a geometric centerof the striking face with the positive direction towards a heel of thegolf club head, a y-axis is a vertical axis orthogonal to the x-axiswith a positive direction towards a top of the golf club head, and az-axis being orthogonal to both the x-axis and the y-axis with apositive direction towards a front of the golf club head. The x-y-zcoordinate system described above shall be the same for all subsequentdiscussions.

FIG. 1 of the accompanying drawings shows a perspective view of a golfclub head 100 in accordance with an embodiment of the present invention.In this perspective view shown in FIG. 1, the golf club head 100 may notlook very different than other golf club heads, but the subsequentfigures and discussion will show that the internal components and thematerial properties of this golf club head 100 allows it to achieveunique performance properties consistent with the present invention.What FIG. 1 does show is a location of a face center 102 of the frontalportion 104 of the golf club head 100 that contains a striking faceinsert. The face center, as shown here and referred to by the currentinvention, relates to the geometric center of the striking face portionof said golf club head 100 measured by the USGA provided face centertemplate as it would be commonly known to a person of ordinary skill inthe golf club art. Attached to the rear of the frontal portion 104 is arear portion 106, which makes up the back end of the golf club head 100.

In this embodiment of the present invention, the frontal portion 104 maygenerally be made out of a steel type material having a density ofbetween about 7.75 g/cc and about 8.00 g/cc, allowing a significantportion of the mass of the golf club head 100 to be concentrated at afrontal bottom region of the golf club head 100. The rear portion 106 ofthe golf club head 100 in this embodiment of the present invention maygenerally be made out of the standard titanium material having a densityof between about 4.00 g/cc and about 5.00 g/cc, allowing the rearportion 106 of the golf club head 100 to be relatively lightweight.However, it should be noted that in alternative embodiments of thepresent invention, the frontal portion 104 may also be made out of astandard titanium material such as TI-6-4, Ti-8-1-1, beta-titanium, orany other type of titanium material without departing from the scope andcontent of the present invention.

In order to illustrate more specific features of the golf club head 100,FIGS. 2 and 3 of the accompanying drawings is provided to give moreinsight into some of the specific inherent characteristics of the golfclub head 200 that will be important to determine its improvedperformance. First off, FIG. 2 of the accompanying drawings, in additionto illustrating a golf club head 200 with a frontal portion 204 and arear portion 206, also shows a Center of Gravity (CG) 210 location alongthe x-z plane on the coordinate system 201. Although the details of theCG location will be discussed in more detail with respect to the inertiaproperties of the golf club head 200, the general direction of thecurrent inventive golf club head 200 is to have a CG location that isstrategically located at a distance back from the frontal portion of thegolf club head 200 to yield the most advantageous results.

More specifically, in the current invention, the CG location rearwardfrom the striking face, identified here as CG-Z is generally betweenabout 25 mm to about 40 mm, more preferably between about 26 mm andabout 38 mm, and most preferably between about 27 mm and about 36 mm,all measured rearward from the face center 202 along the Z axis shown bythe coordinate system 201. In addition to illustrating the CG-Z 212numbers, an alternative measurement method is provided to measure howfar back the CG 210 is located within the club head 200. In thisalternative method, the CG 210 is measured from the shaft axis 215, andthis measurement is illustrated as CG-C 214 is generally measured to bebetween about 10 mm to about 25 mm, more preferably between about 12 mmto about 23 mm, and most preferably between about 14 mm to about 21 mm,all measured rearward from the shaft axis 215 along the Z axis shown bythe coordinate system 201.

It should be noted that the strategic location of the CG 210 locationrearward along the Z axis, irrespective of whether it is measured fromthe face center 202 or the shaft axis 215, is critical to the properfunctionality of the current inventive golf club head 200. If the CG 210location is too far forward, the golf club head 200 can result in a lowMOI-X and MOI-Y as well as too low of a backspin when contacting a golfball to yield desirable results. However, in the alternative, if the CG210 location is too far rearward, the golf club head 200 can produce toomuch spin to yield desirable results. Hence, it can be seen that thecriticality of the CG location rearward of along the Z axis is a finebalance of a very specific range of numbers that can severely hinder theperformance of the golf club head 200 if it deviates from the rangesarticulated above.

FIG. 3 of the accompanying drawings shows another important CG 210measurement that is important to the proper functionality of the currentinvention. More specifically, FIG. 3, in addition to illustrating all ofthe basic components of the golf club head 200 as previously shown, nowintroduces another measurement of the CG 210 location from the shaftaxis 215 along an x-y plane shown by coordinate system 301. Morespecifically, FIG. 3 shows a CG 210 measurement that is perpendicular tothe shaft axis 215 along this x-y plane away from the actual shaft axis215 itself, called CG-B for the purpose of this application. The CG-B ofthe golf club head 210 may generally be between about 32 mm and about 39mm, more preferably between about 33 mm and about 38 mm, and mostpreferably about 35 mm.

In addition to illustrating the very important CG-B measurement of thegolf club head, FIG. 3 of the accompanying drawings also showsmeasurements W1 and W2, indicative of the width of the golf club head200 itself and the width of the face of the golf club head 200respectively. In this embodiment of the present invention, the width ofthe golf club head W1 may generally be between about 130 mm to and about140 mm, more preferably between about 132 mm to about 138 mm, and mostpreferably about 136 mm. The width of the face W2 may generally bebetween about 95 mm and about 105 mm, more preferably between about 97mm and about 103 mm, and most preferably about 100 mm.

Now that the CG location of the golf club head 200 has been defined, theother important features associated with the present invention relatesto the Moment of Inertia (MOI) of the golf club head 200. The MOI of agolf club head generally depicts the ability of the golf club head toresist twisting when it impacts an object at a location that is notaligned with the CG location previously discussed. More specifically,the MOI of a golf club head relates to the ability of the golf club headto resist twisting relative to the CG location. As is well known in theart, the MOI of the golf club head 200 may generally be broken down tothree unique components, relating to the ability of the golf club head200 to resist rotation along three different axes with the origin of thethree axes being coincident with the CG location of the golf club head.The three axes of rotation for which the MOI is generally referredcoincides with the coordinate system 101, 201, and 301 (shown in FIG. 1,FIG. 2, and FIG. 3 respectively), where MOI-X is measured about the Xaxis passing through the CG location, MOI-Y is measured about the Y axispassing through the CG location, and MOI-Z is measured about the Z axispassing through the CG location.

As the previously discussion already hinted, the current inventive golfclub head 200 may generally have a high value for the MOI about the Xand Y axis, while maintaining a low MOI about the Z axis. Morespecifically, the current inventive golf club head 200 may generallyhave a MOI about the X axis (MOI-X) that is greater than about 300kg-mm², more preferably greater than about 310 kg-mm², and mostpreferably greater than about 320 kg-mm² without departing from thescope and content of the present invention. As for MOI about the Y axis(MOI-Y), the present inventive golf club head 200 may generally have aMOI about the Y axis that is greater than about 400 kg-mm², morepreferably greater than about 410 kg-mm², and most preferably greaterthan about 420 kg-mm² all without departing from the scope and contentof the present invention.

While the large MOI number about the X and Y axis discussed previouslyare not necessarily new in the world of golf club head 200 designs, theability to maintain those number while decreasing the MOI about the Zaxis (MOI-Z) and holding the MOI about the Shaft axis (MOI-SA) to aminimum is what makes the present invention. While the majority of thegolf industry are focusing their attention so intently on the ability ofthe golf club head 200 to offer forgiveness on off center hits by tryingto increase the MOI-Y to astronomical numbers, they have failed torecognize the ability of the golf club head 200 to offer more club headspeed and more ball speed by decreasing the MOI about the Z axis (MOI-Z)in concert with the minimization of MOI about the Shaft axis (MOI-SA).The present invention focuses its attention on that very specificunrecognized characteristic, and has developed a golf club head 200design to take advantage and maximize the performance of the golf clubhead 200 by focusing on the MOI about the Z axis. More specifically, agolf club head 200 in accordance with the present invention maygenerally have a MOI about a Z axis that is less than about 268 kg-mm²,more preferably less than about 260 kg-mm², and most preferably lessthan about 250 kg-mm². Additionally, the golf club head 200 maygenerally have a MOI about a Shaft axis that is less than about 850kg-mm².

It should be noted here that the low MOI-Z numbers mentioned abovecannot by itself accurately depict and describe the current invention;as old school golf club heads with much smaller footprint may inherentlyhave a low MOI-Z number, combined with a low MOI-X and MOI-Y number.Hence, it is important to recognize here that the present invention ispredicated on the interrelationship between the different numbersachieved by the MOI-X and MOI-Y numbers as it relates to MOI-Z andMOI-SA, in combination with the CG location articulated above.

In order to capture the essence of the present invention, a ratio can becreated between the MOI-X, MOI-Y, and MOI-Z to help provide one way toquantify this relationship. In one first example, a MOI-X to MOI-Z Ratiocan be created to help quantify the current golf club head 200 asillustrated by Eq. (1) below. In one exemplary embodiment of the presentinvention, the MOI-X to MOI-Z Ratio is greater than about 1.10, morepreferably greater than about 1.20, and most preferably greater thanabout 1.28.

$\begin{matrix}{{{MOI}\text{-}X\mspace{14mu}{to}\mspace{14mu}{MOI}\text{-}Z\mspace{14mu}{Ratio}} = \frac{{MOI}\text{-}X}{{MOI}\text{-}Z}} & {{Eq}.\mspace{14mu}(1)}\end{matrix}$Similarly, a comparable ratio can be established called a MOI-Y to MOI-ZRatio to quantify the current golf club head 200 as illustrate by Eq.(2) below. In one exemplary embodiment of the present invention, theMOI-Y to MOI-Z ratio is greater than about 1.50, more preferably greaterthan about 1.57, and most preferably greater than about 1.68.

$\begin{matrix}{{{MOI}\text{-}Y\mspace{14mu}{to}\mspace{14mu}{MOI}\text{-}Z\mspace{14mu}{Ratio}} = \frac{{MOI}\text{-}Y}{{MOI}\text{-}Z}} & {{Eq}.\mspace{14mu}(2)}\end{matrix}$

As it can be seen from the relationship established by the Eqs (1) and(2) above, the present invention relates to a specific relationshipbetween the MOI of the golf club head 200 with an extra focus onminimizing the MOI-Z about the Z axis while maintaining a high MOI-Y. Inorder to further illustrate this, a graphical representation of therelationship is provided as FIG. 4.

FIG. 4 of the accompanying drawings shows a plot of various data pointsof various golf club head and their respective MOI-Z numbers as well astheir MOI-Y number. In FIG. 4 the X-axis represents the MOI-Y while theY-axis represents the MOI-Z. The data points shown in FIG. 4 have beenseparated into circular dots and asterisks. The circular dots arerepresentative of the data of “prior art” golf club heads, whereas theasterisk data points represent the current invention.

A closer examination of the prior art data points will show that none ofthe golf club heads in the prior art are capable of achieving a MOI-Znumber of lower than 268 kg-mm², for all modern day golf club heads thathave a MOI-Y of greater than 420 kg-mm². However, an even closerexamination of the graph of FIG. 4 will show that as the MOI-Y numbersof the golf club heads exceeds 500 kg-mm², an additional relationshipcan be established to quantify the ability of the present invention toachieve the optimal MOI-Z to MOI-Y relationship. In fact, thatrelationship is shown in FIG. 4 as Y≤0.47x+33. Combining the twoconditions articulated above can result in another unique way toquantify the present invention whereas, for golf club heads having aMOI-Y of between 420 kg-mm² and 500 kg-mm², the golf club head generallyhas a MOI-Z of less than about 268 kg-mm²; however, for golf club headshaving a MOI-Y of greater than 500 kg-mm², the golf club head may have aMOI-Z that satisfies Eq. (3) below:MOI-Z≤(0.47*MOI-Y)+33  Eq. (3)Alternatively speaking, it can be said that in one embodiment of thepresent invention, the golf club head 200 may have a MOI-Z thatsatisfies the relationship MOI-Z≤(0.47*MOI-Y)+33 if the MOI-Y number isgreater than 500 kg-mm², and a MOI-Z that is less than 268 kg-mm² if theMOI-Y number is between 420 kg-mm² and 500 kg-mm².

FIG. 5 of the accompanying drawing introduces another MOI value relatingto a golf club head not previously discussed named MOI-Shaft Axis(MOI-SA). The MOI of a golf club head as it relates to the shaft axis isdefined as the ability of the golf club head to resist twisting uponimpact with a golf ball at a location that is not aligned with the shaftaxis. A golf club head in accordance with the present invention maygenerally have a MOI-SA of less than about 850 kg-mm², more preferablyless than about 800 kg-mm², and most preferably less than about 750kg-mm². The relationship between the MOI-SA and MOI-Z is highlighted inFIG. 5 and is important to the present invention. FIG. 5 of theaccompanying drawings shows that irrespective of the MOI-SA numbers, allof the prior art golf club heads have a MOI-Z of greater than about 268kg-mm², while all of the current inventive golf club heads have a MOI-Zof less than about 268 kg-mm².

FIG. 6 of the accompanying drawings establishes a graphical relationshipbetween the MOI-Y of the golf club head with the newly introducedMOI-SA. As a closer examination of the graph shown in FIG. 6 will show,the current invention is capable of achieving a higher than averageMOI-Y, all while keeping a relatively small MOI-SA. Similar to previousplots, the circular points on the plot will refer to prior art golf clubheads, while the asterisks will refer to the current invention. Hence,it can be seen that the present invention occupies a previouslyunachieved space delineated by an equation Y≥0.52x+147, which when putinto context with the variables used in this plot, yields Eq. (4) below:MOI-Y≥(0.52*MOI-SA)+147  Eq. (4)

FIG. 7 of the accompanying drawings establishes a graphical relationshipbetween the MOI-X of the golf club head with now a familiar MOI-SA. As acloser examination of the graph shown in FIG. 7 will show, the currentinvention is capable of achieving a higher than average MOI-X, all whilekeeping a relatively small MOI-SA. Hence, it can be seen that thepresent invention occupies a previously unachieved space delineated byan equation Y≥0.40x+50, which when put into context with the variablesused in this plot, yields Eq. (5) below:MOI-X≥(0.40*MOI-SA)+50  Eq. (5)

FIG. 8 of the accompanying drawings establishes a graphical relationshipbetween the MOI-Z of the golf club head with a ratio of CG-B/Face Width.Both the measurement for CG-B and Face Width can be found in FIG. 3 ofthe accompanying drawings as well as the accompanying discussion as setforth above. The CG-B measurement is explicitly shown in FIG. 3, whilethe Face Width referred to by the chart in FIG. 8 is shown as W2. Acloser examination of the graph shown in FIG. 8 will show that thecurrent invention is capable of achieving a lower MOI-Z, while keepingthe CG-B/Face Width number fairly consistent above 0.4. CG-B/Face Widthis indicative of the location of the center of gravity while keeping amoderately sized face golf club head.

In the chart shown in FIG. 8, it can be seen that the present inventionoccupies a previously unachieved space delineated by an equationY≤1000x−150, which when put into context with the variable used in thisplot, yields Eq. (6) below:

$\begin{matrix}{{{MOI}\text{-}Z} \leq {\left( {1000*\frac{{CG}\text{-}B}{{Face}\mspace{14mu}{Width}}} \right) - 150}} & {{Eq}.\mspace{14mu}(6)}\end{matrix}$

FIG. 9 of the accompanying drawings establishes a graphical relationshipbetween the MOI-Z of the golf club head with a ratio of CG-B/Head Width.Both the measurement for CG-B and Head Width can be found in FIG. 3 ofthe accompanying drawings as well as the accompanying discussion above.The CG-B measurement is explicitly shown in FIG. 3, while the Head Widthreferred to by the chart in FIG. 9 is shown as W1. A closer examinationof the graph shown in FIG. 9 will show that the current invention iscapable of achieving a lower MOI-Z, while keeping the CG-B/Head Widthnumber fairly consistent above 0.34. CG-B/Head Width is indicative ofthe location of the center of gravity while keeping a moderately sizedhead width of the golf club head.

In the chart shown in FIG. 9, it can be seen that the present inventionoccupies a previously unachieved space delineated by a MOI-Z number thatis lower than 320 kg-mm² combined with a CG-B/Head Width number that isgreater than about 0.34.

FIG. 10 of the accompanying drawings establishes another graphicalrelationship of the performance of a golf club in accordance with anembodiment of the present invention. More specifically, FIG. 10 of theaccompanying drawings shows a relationship between MOI-X/MOI-Z and CG-Z.(MOI-X is used interchangeably with Ixx, MOI-Y is used interchangeablywith Iyy, and finally MOI-Z is used interchangeably with Izz) Thedefinition and measurement for CG-Z of a golf club head can be found inthe earlier discussion relating to FIG. 2 of the accompanying drawings,while the background information establishing MOI-X and MOI-Z havealready been discussed previously. Although the selection of the plotfor the X and Y axis may appear random initially to a person not versedin golf club design, but a closer examination will reveal that therelationship created here is absolutely critical to the properperformance of the present invention. On the Y axis of the plot shown inFIG. 10, a ratio between MOI-X and MOI-Z is created here. This ratiocreated illustrates the ability of the current inventive golf club headto maximize the value of one variable (MOI-X) while minimizing the valueof another variable (MOI-Z); which resonates with the theme of thepresent invention. The CG-Z used in the X axis of the plot shown in FIG.10 is indicative of the CG location of the golf club head rearward fromthe front of the golf club head, and it is desirable to maintain that inthe range described above.

A further examination of the plot shown in FIG. 10 will show that thepresent invention occupies a portion of the graph that was previouslyunachieved. This portion of the graph is delineated from other prior artdata points by an equation Y≥6.7501x−99.30, which when put into contextwith the variable used in this plot, yields Eq. (7) below:

$\begin{matrix}{\frac{{MOI}\text{-}X}{{MOI}\text{-}Z} \geq {\left( {6.7501*{CG}\text{-}Z} \right) - 99.30}} & {{Eq}.\mspace{14mu}(7)}\end{matrix}$

FIG. 11 of the accompanying drawings establishes another graphicalrelationship of a golf club in accordance with an embodiment of thepresent invention by creating a relationship between the MOI-Y/MOI-Z andCG-Z. The definition and measurement for CG-Z of a golf club head can befound in the earlier discussion relating to FIG. 2 of the accompanyingdrawings, while the background information establishing MOI-Y and MOI-Zhave already been discussed previously. Similar to the previousdiscussion, the relationship between MOI-Y and MOI-Z is indicative ofthe ability of a golf club to achieve great forgiveness along the MOI-Yaxis, while minimizing the MOI-Z of a golf club head to achieve a higherball speed, as previously discussed. Similar to previous discussion,FIG. 11 of the accompanying drawings shows that the present invention iscapable of achieving performance characteristics that was previouslyunachieved. This portion of the graph is delineated from other prior artdata points by an equation Y≥11.349x−175.76, which when put into contextwith the variable used in this plot, yields Eq. (8) below:

$\begin{matrix}{\frac{{MOI}\text{-}Y}{{MOI}\text{-}Z} \geq {\left( {11.349*{CG}\text{-}Z} \right) - 175.76}} & {{Eq}.\mspace{14mu}(8)}\end{matrix}$

FIG. 12 of the accompanying drawings establishes another graphicalrelationship of a golf club in accordance with an embodiment of thepresent invention by creating a relationship between the(MOI-X+MOI-Y)/MOI-Z and CG-Z. The definition and measurement for CG-Z ofa golf club head can be found in the earlier discussion relating to FIG.2 of the accompanying drawings, while the background informationestablishing MOI-X, MOI-Y, and MOI-Z have already been discussedpreviously. Similar to the previous discussion, the relationship betweenMOI-X, MOI-Y, and MOI-Z is indicative of the ability of a golf club toachieve great forgiveness along both the MOI-X and MOI-Y axes, whileminimizing the MOI-Z of a golf club head to achieve a higher ball speed,as previously discussed. Similar to previous discussion, FIG. 12 of theaccompanying drawings shows that the present invention is capable ofachieving performance characteristics that was previously unachieved.This portion of the graph is delineated from other prior art data pointsby an equation Y≥18.67x−296.63, which when put into context with thevariable used in this plot, yields Eq. (9) below:

$\begin{matrix}{\frac{\left( {{{MOI}\text{-}X} + {{MOI}\text{-}Y}} \right)}{{MOI}\text{-}Z} \geq {\left( {18.67*{CG}\text{-}Z} \right) - 296.63}} & {{Eq}.\mspace{14mu}(9)}\end{matrix}$

FIGS. 13 through 15 show different exploded and cross-sectional view ofgolf club heads and their internal components that are used to achievethe performance characteristics described above. FIG. 13 shows anexploded perspective view of an exemplary design of a golf club head1300 in capable of achieving the performance characteristics previouslydiscussed. The golf club head 1300 is made out of the essentialcomponents previously discussed in FIG. 1 in terms of a frontal portion1304 and a rear portion 1306. However, this exploded view of golf clubhead 1300 allows additional components to be shown in more detail. Morespecifically, FIG. 13 illustrates that, as often the case in a golf clubhead construction, the frontal portion 1304 may further be comprised outof a separate component called the striking face insert 1320 to form thestriking portion of the golf club head 1300. The rear portion 1306 ofthe golf club head 1300 is where it gets more interesting. In order toachieve the performance numbers above of a higher MOI-Y, a higher MOI-X,and a lower MOI-Z, a significant amount of mass is re-allocated towardsthe center of the golf club head away from the perimeter. In order toachieve this, the present invention utilizes four weighting members thatare all comprised out of a high density material that have a higherdensity than the frontal portion 1304 or the rear portion 1306. The fourweighting members can be separated into a frontal sole weight 1322,frontal internal weight 1324, rear internal weight 1326, and rear soleweight 1328, and these weighting members may all generally have amaterial density of greater than 13 g/cc, more preferably greater thanabout 15 g/cc, and most preferably greater than about 17 g/cc.

It should be noted that in this exemplary embodiment of the presentinvention, all of the weighting members 1322, 1324, 1326, and 1328 areall made out of the same material having the same heavy densitydiscussed previously. However, in alternative embodiments of the presentinvention, different densities of tungsten may be used for differentweighting members depending on the design criteria and desired CGlocation all without departing from the scope and content of the presentinvention.

FIG. 14 of the accompanying drawings shows a cross-sectional view of agolf club head 1400 in accordance with an exemplary embodiment of thepresent invention. The cross-sectional view of the golf club head takenacross a horizontal plane across the face of the golf club head 1400 toallow some of the relationship between the golf club head 1400 and thevarious weighting member 1422, 1424, 1426, and 1428 to be shown moreclearly. In addition to the weighting members, the cross-sectional viewof the golf club head 1400 shown in FIG. 14 also allows the face center1402 and the CG location 1410 to be re-introduced as it relates to theweighting members. It can be seen from this view that at least oneweighting member is located near a central portion of the golf club headin a heel to toe direction, and substantially in line with and behindsaid face center.

FIG. 15 of the accompanying drawings shows a cross-sectional view of agolf club head 1500 in accordance with an exemplary embodiment of thepresent invention taken along a vertical plane that passes through thecenter of the face. This cross-sectional view of the golf club head 1500shown in FIG. 15 provides a little more information on the interworkingrelationship between the components. More specifically, FIG. 15 shows astriking face insert 1520 being located in the frontal portion 1504 ofthe golf club head 1500. In addition to the above, FIG. 15 also showsthat the frontal sole weight 1522 is located in a receptacle that iscreated within the frontal portion 1504. Although not shown in thiscross-sectional view in FIG. 15, the frontal internal weight is alsolocated in the frontal portion 1504. Attached to the rear of the frontalportion 1504 is the rear portion 1506. The rear portion 1506 forms theaft body portion of the golf club head 1500, and contains the rearinternal weight 1526 and the rear sole weight 1528. These weightingmembers, combined with the unique materials used to form the frontalportion 1504 and the rear portion 1506, allow the golf club head 1500 toachieve the unique performance characteristics outlined previously.

FIGS. 16 through 20 show various perspective and cross-sectional viewsof a golf club head 1600 in accordance with an alternative embodiment ofthe present invention that is capable of achieving the performance goalspreviously mentioned. Similar to the previous embodiment illustrated byFIGS. 1-3 and 13-15, a lot of weighting member is located near thecenter of the golf club head 1600 in a heel to toe orientation along thex-axis behind the face center 1602 to help minimize the MOI-Z of thegolf club head 1600.

More specifically, FIG. 16 of the accompanying drawings shows aperspective view of a golf club head 1600 in accordance with thisalternative embodiment of the present invention. Although not much canbe gleamed from this perspective view of the golf club head 1600, itdoes lay the ground work for the subsequent discussion relating to thisparticular embodiment of the present invention. Finally, FIG. 16,similar to previous figures that illustrate a golf club head, provides acoordinate system 1601 to guide the subsequent discussions.

FIG. 17 of the accompanying drawings shows a top view of a golf clubhead 1600 in accordance with this alternative embodiment of the presentinvention. In this top view, a couple of familiar dimensions arereintroduced here. First and foremost, the top view of the golf clubhead 1600 shown in FIG. 17 allows the relationship between the facecenter 1602 and the CG 1610 to be shown in more detail. When measuredalong the Z-axis, the measurement CG-Z is shown as 1612. The location ofthe CG, when referenced against the shaft axis 1615 yields another wayto measure the CG location along the Z-axis called CG-C 1614. The numberranges for the CG-Z 1612 and CG-C 1614 measurements are not muchdifferent from previous discussions, but this embodiment of the presentinvention provides an alternative way to achieve those targets with aslightly different construction without the need for a multi-materialchassis.

FIG. 18 of the accompanying drawings shows a frontal view of a golf clubhead 1600 in accordance with this alternative embodiment of the presentinvention. In this frontal view, we can see another feature utilized bythe present embodiment to help achieve the performance criteria of thecurrent invention. More specifically, FIG. 18 shows that in thisembodiment of the present invention, in order to minimize the MOI-Z ofthe golf club head 1600, weight is removed from the extremities of thegolf club head 1600 via a reshaping of the contour at the toe portion ofthe golf club head 1600. This reshaping of the contour at the toeportion of the golf club head 1600 not only removes weight from theextremities, but also tightens up the face profile of the golf club head1600 to create a unique performing golf club head 1600.

In addition to illustrating this toe contour profiling, FIG. 18 alsoshows a CG-B 1616 measurement relating to the shaft axis 1615 similar tothe previous discussion. Once again, the CG-B 1616 measurement range isin line as the previous discussion have mentioned, and does not deviatemuch from the design intent of the present invention.

FIG. 19 of the accompanying drawings shows a cut open cross-sectionalview of a golf club head 1600 in accordance with this alternativeembodiment of the present invention taken along a horizontal plane. Inthis embodiment of the present invention, the overarching theme ofplacing the weights along the central portion of the golf club head 1600reemerges again. More specifically, the golf club head 1600 furthercomprises of a frontal internal weight 1624 and a rear internal weight1626. These weights, however, different from prior embodiments of thepresent invention in that they can be made out of the same material asthe body portion of the golf club head 1600 such as titanium and bedirectly cast into the body without departing from the scope and contentof the present invention. These weighting members 1624 and 1626 may alsobe made out of a tungsten type material having a total weight of 20-23grams to further improve the performance of the golf club head 1600without departing from the scope and content of the present invention.

FIG. 20 of the accompanying drawings provides another cross-sectionalcut open view of the golf club head 1600 in accordance with analternative embodiment of the present invention taken along a verticalplane. Once again, the measurements here are very similar to thediscussion previously relating to prior embodiments and the CG-Z 1612number remain within the same range as the prior discussion. Thiscross-sectional cut open view of the golf club head 1600 taken alongthis line allows the profile and geometry of the frontal internal weight1624 and the rear internal weight 1626 to be shown more clearly andtheir relationship together with the body portion of the golf club head1600.

Referring to FIGS. 21-25 the golf club head 2000 has all of the mass andinertial properties discussed above. Further, the golf club head 2000comprises frontal portion comprising a striking face 2001 having a facecenter FC, a crown on the upper portion of the golf club head 2000 and asole on the bottom portion of the golf club head 2000. The golf clubhead 2000 further comprises a crown return 2002 and a sole return 2003as part of the frontal portion and a central body member 2004 that areall formed of metal. The central body member 2004 is located near thecentral portion of the golf club head 2000 in a heel-to-toe orientation,substantially in line along the z-axis as set forth above, and extendsfrom the crown return 2002 and the sole return 2003 to a back edge 2005of the golf club head. The golf club head 2000 is further comprised of aheel body member 2006 made of a non-metallic material and coupled to aheel side of the central body member 2004 and the crown return 2002 andthe sole return 2003. The golf club head 2000 also includes a toe bodymember 2007 made of a non-metallic material and coupled to a toe side ofthe central body member 2004 and the crown return 2002 and the solereturn 2003. The heel body member 2006 and the toe body member 2007 areessentially taco shell shaped, taco-shaped, in that they form a portionof the crown and a portion of the sole such that they have a c-shapedcross section. Preferably, as set forth above, the metal portions can beformed of a standard titanium materials such as TI-6-4, Ti-8-1-1,beta-titanium, and others that have a specific gravity of about 4 g/ccto 5 g/cc. Alternatively, the metal portions can be formed of a standardsteel materials that have a specific gravity of about 7 g/cc to 9 g/ccThe heel body member 2006 and the toe body member 2007 are preferablyformed of a standard composite fiber composite laminate, chopped fibercomposite generally referred to as fiber-reinforced plastic (FRP), or acomposite material such as those disclosed in U.S. Publication No.2015-0360094, which is incorporated by reference in its entirety herein.Alternatively, the heel body member 2006 and the toe body member 2007are preferably formed of structural material having a density of lessthan 3.0 g/cc such as a thermoplastic material such as those disclosedin U.S. application Ser. No. 16/528,210, filed on Jul. 31, 2019, whichis incorporated by reference in its entirety herein, polyetherimide(PEI), polyether ether ketone (PEEK), polyphenylene sulfide (PPS),polysulfone (PSU), polyacryletherketone (PEAK), polyetherketoneketone(PEKK) and polyvinyl chloride (PVC). The heel body member 2006 and thetoe body member 2007 are preferably formed by compression molding,injection molding or 3D printing.

The golf club head 2000 further has a center of gravity CG that islocated a distance back from the face center, CG-z, a vertical distanceup from the ground plane, CG-y, a perpendicular distance from the shaftaxis, GC-SA, a horizontal distance from the face center toward the heelside, CG-x and a distance back, parallel to the z-axis, from the shaftaxis, CG-C. As stated above, in the current invention, the CG-z isgenerally between about 25 mm to about 40 mm, more preferably betweenabout 26 mm and about 38 mm, and most preferably between about 27 mm andabout 36 mm, all measured rearward from the face center FC along thez-axis shown by the coordinate system above. In addition to the CG-znumbers, an alternative measurement method is provided to measure howfar back the CG is located within the club head 2000. In thisalternative method, the CG is measured from the shaft axis SA, and thismeasurement is illustrated as CG-C is generally measured to be betweenabout 10 mm to about 30 mm, preferably 10 mm to 25 mm, more preferablybetween about 12 mm to about 28 mm, and more preferably 12 mm to 23 mmand most preferably between about 14 mm to about 21 mm, all measuredrearward from the shaft axis SA along the z-axis direction shown by thecoordinate system above.

As stated above, it is important that the strategic location of the CGrearward along the z-axis be correct, irrespective of whether it ismeasured from the face center FC or the shaft axis SA, for the properfunctionality of the current inventive golf club head 2000. If the CGlocation is too far forward, the golf club head 2000 can have a lowMOI-X and MOI-Y and low backspin when contacting a golf ball. However,in the alternative, if the CG location is too far rearward, the golfclub head 2000 can produce too much spin to yield desirable results.Hence, the CG location rearward along the z-axis is important for theperformance of the golf club head 2000.

FIG. 22 of the accompanying drawings shows another important CGmeasurement that is important to the proper functionality of the currentinvention. More specifically, FIG. 22, in addition to illustrating allof the components of the golf club head 2000 as previously discussed,shows another measurement of the CG location from the shaft axis SAalong an x-y plane. More specifically, FIG. 22 shows a CG measurementthat is perpendicular to the shaft axis SA along this x-y plane, calledCG-B for the purpose of this application. The CG-B of the golf club head2000 may generally be between about 32 mm and about 39 mm, morepreferably between about 33 mm and about 38 mm, and most preferablyabout 35 mm.

As shown in FIG. 22, the golf club head 2000 can further include acentral support member 2010 such as wall member 2010 that is coupled toa crown portion of the central body member 2004 and a sole portion ofthe central body member 2004. The wall member 2010 preferably has athickness t that is between 0.2 mm and 5 mm, and more preferably,between about 0.4 mm and 2 mm.

As shown in FIG. 23, the central body member 2004 preferably has a heelside circumferential attachment edge 2011 and a toe side circumferentialattachment edge 2012 for coupling the heel body member 2006 and the toebody member 2007, respectively, to the central body member 2004 and thecrown return 2002 and the sole return 2003. The heel sidecircumferential attachment edge 2011 and the toe side circumferentialattachment edge 2012 preferably extend from approximate the crown return2002 and the sole return 2003 to a back edge 2005 of the golf club head2000.

As shown in FIG. 24, the golf club head 2000 can further include atleast one weight member 2008 or 2009, and more preferably, includes twoweight members 2008 and 2009. The first weight member 2008 is located onthe sole portion of the club head, forward near the striking face 2001and the second weight member 2009 is located on the sole portion of theclub head, aft near the back edge 2005. At least one of the weightmembers 2008 and 2009 may generally have a material density of greaterthan 13 g/cc, and more preferably greater than about 15 g/cc. The weightmembers 2008 and 2009 preferably have a mass of between about 0 gramsand 50 grams, more preferably between about 3 grams and 35 grams andmost preferably between 5 grams and 25 grams. In one embodiment of theinvention, the first weight member 2008 has a mass of at least two timesthe mass of the second weight member 2009. In another embodiment of theinvention, the first weight member 2008 has a mass of less than half themass of the second weight member 2009. More preferably, the weightmembers 2008 and 2009 are interchangeable so that the CG can be adjustedforward and rearward to control the club head's launch and spincharacteristics. Furthermore, the center of the first weight member 2008is preferably located less than 30 mm from the striking face 2001 alongthe z-axis and the center of the second weight member 2009 is preferablylocated less than 20 mm from the back edge 2005 along the z-axis suchthat the interchangeable weights can have a maximum effect on the spinand launch characteristics of the club head.

In one embodiment of the present invention and as shown in FIG. 25, thecentral support member or wall member 2010 is coupled to a crown portionof the central body member 2004 and a sole portion of the central bodymember 2004 and extends between the first and second weight members 2008and 2009. The central support member 2010 preferably has a maximumheight H parallel to the y-axis and a maximum depth D parallel to thez-axis. The depth D is preferably greater than the maximum height H.Also shown in FIG. 25, the heel side circumferential attachment edge2011 and the toe side circumferential attachment edge 2012 for couplingthe heel body member 2006 and the toe body member 2007 to the centralbody member 2004 can include a plurality of recesses or apertures 2013that adhesive can enter into and better lock the components together.Alternatively, the heel side circumferential attachment edge 2011 andthe toe side circumferential attachment edge 2012 may have a pluralityof protrusions on the outer surface to create a gap between the heelbody member 2006 and the toe body member 2007 to the central body member2004 such that an adhesive can fill the gap and create a stronger bondtherebetween.

In another embodiment of the present invention, the golf club head'scentral support member 2010 can be comprised of a plurality of strutmembers 2014, 2015, 2016, 2017, 2018 and 2019 that extend form the crownto the sole of the central body member 2004 between the two weightmembers 2008 and 2009. Again, the central support member 2010 preferablyhas a maximum height H parallel to the y-axis and a maximum depth Dparallel to the z-axis. The depth D is preferably greater than themaximum height H. Preferably, a first angled strut member 2014 extendsfrom a crown portion of the central body member 2004 to the sole and asecond angled strut member 2015 extends from a sole portion of thecentral body member 2004 to the crown, and the first and second angledstrut members 2014 and 2015 preferably cross each other. Preferably, thefirst and second angled strut members 2014 and 2015 extend at an angle αof between 15 degrees and 75 degrees from the y-axis and an angle β ofbetween 15 degrees and 75 degrees from the z-axis. More preferably, thefirst and second angled strut members 2014 and 2015 extend at an angle αof between 15 degrees and 45 degrees from the y-axis and an angle β ofbetween 45 degrees and 75 degrees from the z-axis. The golf club head2000 can further comprise a third angled strut member 2016 that extendsfrom a crown portion of the central body member 2004 to the sole and afourth angled strut member 2017 that extends from a sole portion of thecentral body member 2004 to the crown, and the third and fourth angledstrut members cross each other. The third and fourth angled strutmembers also extend at angles α and β of between 15 degrees and 75degrees from both the y-axis and the z-axis respectively. Preferably,the third angled strut member 2016 is coupled to the first angled strutmember 2014 at the crown and the fourth angled strut member 2017 iscoupled to the second angled strut member 2015 at the sole. Furthermore,preferably, the third angled strut member 2016 is substantially parallelto the second angled strut member 2015 and the fourth angled strutmember 2017 is substantially parallel to the first angled strut member2014. The golf club head 2000 can further comprise a vertical strutmember 2018 extending vertically, substantially parallel to the y-axis,between the first angled strut member 2014 and the second angled strutmember 2015 approximate the first weight member 2008. Even morepreferably, the golf club head 2000 can further comprise a secondvertical strut member 2019 extending vertically, substantially parallelto the y-axis, between the fourth angled strut member 2017 and the thirdangled strut member 2016 adjacent to the second weight member 2009.

The advantage of the central support member 2010, either in the form ofthe wall member 2010 or the angled strut members 2014, 2015, 2016 and2017 is that it prevents the crown portion of the central body member2004 from deflecting relative to the sole portion of the central bodymember 2004 in the y-axis and also prevents the portions from shearingwith respect to each other in the z-axis.

The advantage of multiple weight members 2008 and 2009 is that theweight members can have equal mass, for example between 10 and 15 gramseach, such that the CG of the club head 2000 is in a neutral position.However, the weight members 2008 and 2009 can also be comprised of aheavy weight, for example greater than 15 grams, and a light weight, forexample less than 10 grams, such that the CG can be moved forward orback depending on the placement of the weights. With the heavy weightlocated in the aft weight member 2009, the MOI-Y is increased and ispreferably greater than about 450 kg-mm². Thus, in a preferred golf clubhead 2000, the MOI-Y is greater than or equal to approximately 2 timesthe MOI-Z. Conversely, when the heavy weight is in the forward weightmember 2008, the CG-C can be significantly decreased. For example, apreferred golf club head 2000 can have a GC-C of between 14 mm to 21 mm.

The advantages of the club head 2000 discussed above can also apply tofairway woods and hybrids. In those embodiments, it is understood thatthe numerical values for the club properties will be lower and the metalwill be generally steels and high strength steels known in the art.However, the construction of the golf club head 2000 can be easilyapplied to these smaller heads.

Referring to FIGS. 27-29 the golf club head 2000 has all of the mass andinertial properties discussed above. Further, the golf club head 2000comprises frontal portion comprising a variable thickness striking face2001 having a maximum thickness at the face center FC, a crown on theupper portion of the golf club head 2000 and a sole on the bottomportion of the golf club head 2000. The golf club head 2000 furthercomprises a crown return 2002 and a sole return 2003 adjacent thestriking face 2001 as discussed above and a central body member 2004that are all formed of metal. The central body member 2004 is locatednear the central portion of the golf club head 2000 in a heel-to-toeorientation, substantially in line along the z-axis as set forth above,and extends from the crown return 2002 and the sole return 2003 to aback edge 2005 of the golf club head 2000. As discussed above, the golfclub head 2000 is further comprised of a heel body member 2006 made of anon-metallic material and coupled to a heel side of the central bodymember 2004 along the heel edge 2011 and a toe body member 2007 made ofa non-metallic material is coupled to a toe side of the central bodymember 2004 along the toe edge 2012. The central body member 2004 caninclude a plurality of protrusions 2013 a that create an adhesive filledgap and better lock the components together. The heel body member 2006and the toe body member 2007 are essentially taco shell shaped,taco-shaped, in that they form a portion of the crown and a portion ofthe sole such that they have a c-shaped cross section. Preferably, asset forth above, the metal portions can be formed of a standard titaniummaterials such as TI-6-4, Ti-8-1-1, beta-titanium, and others that havea specific gravity of about 4 g/cc to 5 g/cc. The heel body member 2006and the toe body member 2007 are preferably formed of a standardcomposite fiber composite laminate, chopped fiber composite generallyreferred to as fiber-reinforced plastic (FRP), or a composite materialsuch as those disclosed in U.S. Publication No. 2015-0360094, which isincorporated by reference in its entirety herein. Alternatively, theheel body member 2006 and the toe body member 2007 are preferably formedof a thermoplastic material such as those disclosed in U.S. applicationSer. No. 16/528,210, filed on Jul. 31, 2019, which is incorporated byreference in its entirety herein, polyetherimide (PEI), polyether etherketone (PEEK), polyphenylene sulfide (PPS), polysulfone (PSU),polyacryletherketone (PEAK), polyetherketoneketone (PEKK) and polyvinylchloride (PVC). The heel body member 2006 and the toe body member 2007are preferably formed by compression molding, injection molding or 3Dprinting.

In a most preferred embodiment, the heel body member 2006 and the toebody member 2007 are preferably formed from a high crystallinity PPS,that is a PPS in which the crystallinity is greater than 40%, and morepreferably, greater than about 50% as measured using differentialscanning calorimetry (DSC) at a heating rate of 20° C./min. Thecrystallinity percentage can be calculated using the following equation:% crystallinty=ΔH _(sample) /ΔH _(reference)×100where: ΔH_(sample) is the sample melting enthalpy with unknowncrystallinity percentage and ΔH_(reference) is the sample meltingenthalpy with the known crystallinity. For PPS, 76.5 J/g may be utilizedas the ΔH_(reference).

In order to increase the crystallinity level in PPS, it is recommendedthat the material be injection molded into molds that are at atemperature of greater than 115° C. and more particularly in a mold thatis between about 125° C. and 135° C. In the most preferred embodiment,the PPS crystallinity is between about 50% and 70%. The materialpreferably has a uniform thickness of about 0.5 mm to about 2 mm.However, in one embodiment, the toe body member 2007 has a thicknessthat is less than the thickness of the heel body member 2006. In anotherembodiment, the toe body member 2007 and the heel body member 2006 varysuch that they are thinnest on the crown portion and thicker on the soleportion. In this embodiment, the crown portions of the toe body member2007 and the heel body member 2006 have a thickness that is preferablybetween about 0.5 mm and 1 mm and the sole portions of the toe bodymember 2007 and the heel body member 2006 are between about 1 mm and 2mm thick.

The golf club head 2000 further has a center of gravity CG that islocated a distance back from the face center, CG-z, a vertical distanceup from the ground plane, CG-y, a perpendicular distance from the shaftaxis, GC-SA, a horizontal distance from the face center toward the heelside, CG-x and a distance back, parallel to the z-axis, from the shaftaxis, CG-C. As stated above, in the current invention, the CG-z isgenerally between about 25 mm to about 40 mm, more preferably betweenabout 26 mm and about 38 mm, and most preferably between about 27 mm andabout 36 mm, all measured rearward from the face center FC along thez-axis shown by the coordinate system above. In addition to the CG-znumbers, an alternative measurement method is provided to measure howfar back the CG is located within the club head 2000. In thisalternative method, the CG is measured from the shaft axis SA, and thismeasurement is illustrated as CG-C is generally measured to be betweenabout 10 mm to about 25 mm, more preferably between about 12 mm to about23 mm, and most preferably between about 14 mm to about 21 mm, allmeasured rearward from the shaft axis SA along the z-axis shown by thecoordinate system above.

As stated above, it is important that the strategic location of the CGlocation rearward along the z-axis be correct, irrespective of whetherit is measured from the face center FC or the shaft axis SA, for theproper functionality of the current inventive golf club head 2000. Ifthe CG location is too far forward, the golf club head 2000 can have alow MOI-X and MOI-Y and low backspin when contacting a golf ball.However, in the alternative, if the CG location is too far rearward, thegolf club head 2000 can produce too much spin to yield desirableresults. Hence, the CG location rearward along the z-axis is importantfor the performance of the golf club head 2000.

As shown in FIGS. 29 and 31, the weight member 2008 has less mass thanweight member 2009 and is preferably made from steel (or at least amaterial that has a lower density that the density of weight member2009). The first weight member 2008 can be located on the forwardportion of the sole return 2003, near the striking face 2001 and thesecond weight member 2009 located on the sole portion of the golf clubhead 2000, aft near the back edge 2005. At least one of the weightmembers 2008 and 2009 may generally have a material density of greaterthan 13 g/cc, more preferably greater than about 15 g/cc, and mostpreferably about 17 g/cc. Preferably, at least one of the weight members2008 and 2009 may generally have a material density of greater than 2g/cc and less than about 9 g/cc, and most preferably between about 4g/cc and about 8 g/cc. The weight members 2008 and 2009 preferably havea mass of between about 0 grams and 50 grams, and more preferablybetween about 5 grams and 25 grams. In one embodiment of the invention,the first weight member 2008 has a mass of at least two times the massof the second weight member 2009. In another embodiment of theinvention, the first weight member 2008 has a mass of less than half themass of the second weight member 2009. More preferably, the weightmembers 2008 and 2009 are the same shape and volume such that they areinterchangeable so that the CG of the golf club head 2000 can beadjusted forward and rearward to control the club head's launch and spincharacteristics. Furthermore, the center of the first weight member 2008is preferably located less than 30 mm from the striking face 2001 alongthe z-axis direction and the center of the second weight member 2009 ispreferably located less than 20 mm from the back edge 2005 along thez-axis direction such that the interchangeable weights can have amaximum effect on the spin and launch characteristics of the club head.More preferably, the center of the first weight member 2008 ispreferably located less than 25 mm from the striking face 2001 along thez-axis direction and the center of the second weight member 2009 ispreferably located less than 20 mm from the back edge 2005 along thez-axis direction.

As shown in FIG. 32, the first weight member 2008 is preferablyreleasably coupled to the sole return 2003 portion of the golf club head2000 by a fastener 2020. The first weight member 2008 may generally havea material density of greater than 4 g/cc, more preferably greater thanabout 7 g/cc, and most preferably between about 7 g/cc and 8 g/cc. Thefirst weight member preferably has a light side 2021 and a heavy side2022. The heavy side 2022 is preferably substantially solid and as shownin FIGS. 29 and 31 is the side identified with indicia such as with adot. In a preferred embodiment, the first weight member 2008 has ahollow portion 2023 that forms the light side 2021 of the weight member2008.

As shown in FIG. 33, the second weight member 2009 is also preferablyreleasably coupled to the sole portion of the central body member 2004portion of the golf club head 2000 by a fastener 2025. The second weightmember 2009 may generally have a material density of greater than 13g/cc, more preferably greater than about 15 g/cc, and most preferablygreater than or equal to about 17 g/cc. The second weight member 2009preferably has a light side 2026 and a heavy side 2027. The heavy side2027 is preferably substantially solid and as shown in FIGS. 29 and 31is the side identified with indicia such as with a dot. In a preferredembodiment, the weight member 2009 has a hollow portion 2028 that formsthe light side 2026 of the second weight member 2009.

More preferably, at least one or both of the weight members 2008 or 2009are comprised of a light side 2021 and 2026 that includes a hollowportion 2023 and 2028 and a heavy side 2022 and 2027 that issubstantially solid or is solid enough that the mass on the heavy sideis greater than the mass on the light side. Alternatively, at least oneor both of the weight members 2008 or 2009 are comprised of a light side2021 and 2026 that includes a hollow portion 2023 and 2028 that can befilled with a material having a density of less than 4 g/cc and a heavyside 2022 and 2027 that is a hollow portion that is filled with amaterial having a density of greater than about 7 g/cc and morepreferably greater than or equal to about 15 g/cc. As shown in FIGS. 29and 31, the weight member 2008 has less mass than weight member 2009 andis preferably made from steel (or at least a material that has a lowerdensity that the density of weight member 2009). More preferably, thefirst weight member 2008 has a mass of about 7 g and 14 g and the secondweight member has a mass of between about 15 g and 22 g. Mostpreferably, the first weight member 2008 and the second weight member2009 can be interchanged in the front and aft locations as shown inFIGS. 29 and 31 to move the CG-C by approximately 1 mm to 5 mm and mostpreferably by about 2.5 mm to 3.5 mm. In the most preferred embodiment,the CG-C can be between about 14 mm and 21 mm when the first weightmember 2008 is in the aft location adjacent the back edge 2005 and theCG-C can be between about 22 mm and 30 mm when the first weight member2008 is in the forward position adjacent the striking face 2001.Further, the first weight member 2008 and the second weight member 2009preferably have approximately the same difference in mass between thelight sides 2021 and 2026 and the heavy sides 2022 and 2027. Preferably,the difference in mass between the light sides 2021 and 2026 and theheavy sides 2022 and 2027 is between about 4 g and 8 g. Thus, if one ofthe weight members has the heavy side toward the heel in the x-axisdirection and the other has the heavy side toward the toe in the x-axisdirection, the CG of the golf club head 2000 can be neutral in thex-axis direction as shown in FIG. 29. However, if the weight membershave both of their heavy sides 2022 and 2027 toward the toe or the heelin in the x-axis direction, the CG can be moved away from the neutralposition along the x-axis direction toward the toe or heel,respectively. Preferably, the golf club head CG can be moved at least0.5 mm toward the toe or the heel from the neutral location and morepreferably, between about 0.7 mm and 1.5 mm. As shown in FIG. 31, boththe first weight member 2008 and the second weight member 2009 have theheavy sides 2022 and 2027 toward the toe in the x-axis direction suchthat the golf club head CG is moved toward the toe by about 1 mm fromthe neutral position GC-n. These weight members can both be rotatedabout the fastener such that the CG is moved toward the heel by about 1mm from the neutral position CG-n and 2 mm from the far toe CG positionas shown in FIG. 31.

FIGS. 34 through 37 show different perspective and cross-sectional viewsof golf club heads and their internal components that are used toachieve the performance characteristics described above. FIG. 34 shows aperspective view of an exemplary design of a golf club head 3000 thatcapable of achieving the performance characteristics previouslydiscussed with respect to the embodiments in FIGS. 1-3 and 13-15 inparticular. The golf club head 3000 is comprised of the essentialcomponents previously discussed in FIGS. 1 and 13 in terms of a frontalportion having a striking face 3001, a crown return 3002 and a solereturn 3003 and a rear portion 3004 comprised of an aft body. In orderto achieve the performance numbers above of a higher MOI-Y, a higherMOI-X, and a lower MOI-Z, a significant amount of mass is allocatedtowards the center of the golf club head away from the perimeter. Inorder to achieve this, the present invention utilizes two weightingmembers that are preferably comprised of high density materials thathave a higher density than the frontal portion 3001, 3002 and 3003 andthe rear portion 3004. Preferably, as set forth above, the frontalportion 3001, 3002 and 3003 can be formed of a standard titaniummaterial such as TI-6-4, Ti-8-1-1, beta-titanium, and others that have adensity of about 4 g/cc to 5 g/cc. The rear portion 3004 is preferablyformed of a standard composite fiber composite laminate, chopped fibercomposite generally referred to as fiber-reinforced plastic (FRP), or acomposite material such as those disclosed in U.S. Publication No.2015-0360094, which is incorporated by reference in its entirety herein.Alternatively, the rear portion 3004 is preferably formed of structuralmaterial having a density of less than 3.0 g/cc such as a thermoplasticmaterials such as those disclosed in U.S. application Ser. No.16/528,210, filed on Jul. 31, 2019, which is incorporated by referencein its entirety herein, polyetherimide (PEI), polyether ether ketone(PEEK), polyphenylene sulfide (PPS), polysulfone (PSU),polyacryletherketone (PEAK), polyetherketoneketone (PEKK) and polyvinylchloride (PVC). The rear portion 3004 is preferably formed bycompression molding, injection molding or 3D printing. Additionally, thegolf club head 3000 includes a sole plate member 3006 secured to anouter surface of the rear portion 3004. In a preferred embodiment, thesole plate member 3006 is also formed from standard titanium materialssuch as TI-6-4, Ti-8-1-1, beta-titanium, and others that have a densityof about 4 g/cc to 5 g/cc. In another preferred embodiment, the soleplate member 3006 is formed from stainless steel or similar materialhaving a density of about 7 g/cc to 8 g/cc.

The golf club head 3000 also includes weight members 3008 and 3009. In afirst embodiment, the weight members 3008 and 3009 can have equal mass,for example between 10 and 15 grams each, such that the CG of the clubhead 3000 is in a neutral position along the z-axis direction. However,the weight members 3008 and 3009 can also be comprised of a heavyweight, for example greater than 15 grams, and a light weight, forexample less than 10 grams, such that the CG can be moved forward orback along the z-axis direction depending on the placement of theweights. With the heavy weight located in the aft weight member 3009,the MOI-Y is increased and is preferably greater than about 450 kg-mm².Thus, in a preferred golf club head 3000, the MOI-Y is greater than orequal to approximately 2 times the MOI-Z. Conversely, when the heavyweight is in the forward weight member 3008, the CG-C can besignificantly decreased. For example, a preferred golf club head 3000can have a GC-C of between 14 mm to 21 mm.

Referring to FIG. 35, the golf club head 3000 further includes aninternal rib member 3010 that is located in the frontal portion. The ribmember 3010 is preferably located near or at the overlapping juncture ofthe frontal portion and the rear portion 3004. Preferably, the depth DDof the golf club head from the leading edge LE to the back edge 3005 isbetween 105 mm and 125 mm, and more preferably between about 118 mm and122 mm. The distance of the crown return DCR from the leading edge towhere the crown return 3002 abuts the rear portion 3004 is preferablyabout 20 mm and 35 mm and more preferably between about 30 mm and 34 mm.The distance of the sole return DSR from the leading edge to where theback end of the sole return 3003 is preferably about 24 mm and 44 mm andmore preferably between about 35 mm and 42 mm. The rib member 3010 istherefore preferably located a distance from the leading edge that isbetween the DCR and the DSR or between 20 mm and 44 mm. Most preferably,the rib member 3010 is angled such that the distance from the leadingedge to the crown portion of the rib member 3010 (at the center of thecrown in the heel-to-toe direction, back from the face center) DRC isless than the distance from the leading edge to the sole portion of therib member 3010 (at the center of the sole in the heel-to-toe direction,back from the face center) DRS. More preferably, DRC is preferablybetween 22 mm and 33 mm and DRS is between 26 mm and 42 mm and is atleast 10% greater than DRC. Thus, the rib member 3010 forms an angleα_(R) that is between about 2° and 10° from the vertical plane at theDRC to a point on the sole at the DRS. The rib member 3010 has a ribheight RH (the height of the rib member from the inner surface of thefrontal portion) that also preferably varies from the crown center tothe sole center and at the heel and toe. Most preferably, the rib heightRH is between about 2 mm and 8 mm and is greatest at the sole center andshortest at the heel and toe. Most preferably, the rib member 3010 has arib height RH of about 5 mm at the sole center, 4 mm at the crown centerand is 3 mm to 3.5 mm at the heel and toe.

The center of the first weight member 3008 is preferably located adistance DW1 from the leading edge LE of about 15 mm to 25 mm. Thecenter of the second weight member 3009 is preferably located a distanceDW2 from the leading edge LE of about 80 mm to 115 mm.

Referring to FIGS. 36 and 37, the second weight member 3009 is shown ina close-up cross-sectional view. The second weight member 3009 iscomprised of an internal weight member 3021 and an external weightmember 3022 with a fastener 3020 coupling the members together to therear portion 3004. The first weight member 3008 preferably has a similarconstruction but would secure about the frontal portion on the solereturn 3003. Most preferably, the first weight member 3008 and thesecond weight member 3009 have similar shaped external weight members3022 that can be interchanged. In this embodiment, the internal weightmember 3021 and the external weight member also secure the sole platemember 3006 to the rear portion 3004 by having the rear portion 3004 andthe sole plate member 3006 compressed between the internal weight member3021 and the external weight member 3022. In the weight embodiment shownin FIG. 37, the sole plate member 3006 and the internal weight member3021 are also threaded so that they can be coupled to the rear portion3004 before the external weight member 3022 is couple by the fastener3020.

Referring to FIGS. 38-41, another embodiment of a rear portion 4004 isshown with a pinch weight member 4009 secured near the back edge 4005that is used to achieve the performance characteristics described above.The pinch weight member 4009 is similar to the second weight member 3009discussed above. The pinch weight member 4009 is comprised of aninternal weight member 4021 and an external weight member 4022 with afastener 4020 coupling the members together to compress the rear portion4004. A first weight member, not shown, preferably has a similarconstruction, but would secure about a frontal portion, also not shown.In the weight embodiment shown in FIG. 41, the sole portion 4012 iscompressed between the internal weight member 4021 and a weightretaining pocket 4023 which are also threaded so that they can becoupled to the rear portion 4004 before the external weight member 4022is coupled to the weight retaining pocket 4023 by the fastener 4020. Theexterior surface of the weight retaining pocket 4023 is cylindrical withtreads and the interior surface is preferably hexagonal or other polygonand matches the shape of the the exterior weight member 4022 such thatthe exterior weight member 4022 cannot rotate in the weight retainingpocket 4023.

In a preferred embodiment, the rear portion 4004 is formed from a crownportion 4011 and a sole portion 4012 that can be coupled by a jointconnector 4013. The crown portion 4011 and the sole portion 4012 arepreferably injection molded separately and then coupled by the jointconnector 4013. The materials for the crown portion 4011 and the soleportion 4012 are preferably the same and the material for the jointconnector is preferably the same or is at least compatible such that iteasily joins to the crown portion 4011 and the sole portion 4012.

In a most preferred embodiment, the rear portion 4004 is preferablyformed from a high crystallinity PPS, that is a PPS in which thecrystallinity is greater than 40%, and more preferably, greater thanabout 50% as measured using differential scanning calorimetry (DSC) at aheating rate of 20° C./min. In order to increase the crystallinity levelin PPS, it is recommended that the material be injection molded intomolds that are at a temperature of greater than 115° C. and moreparticularly in a mold that is between about 125° C. and 135° C. In themost preferred embodiment, the PPS crystallinity is between about 50%and 70%. Preferably, the PPS can be formed without any filler or cancontain a filler such as glass filler. In the glass filler PPSembodiment, the PPS preferably has greater than about 20% glass filler,more preferably between about 20% and 50% and most preferably betweenabout 30% and 50%. The material preferably has a uniform thickness ofabout 0.5 mm to about 2 mm. However, in one embodiment, the heel side4007 has a thickness that is less than the thickness of the toe side4006. In another embodiment, the thickness varies such that it isthinnest on the crown portion 4011 and thicker on the sole portion 4012.In this embodiment, the crown portion 4011 has a thickness that ispreferably between about 0.5 mm and 1 mm and the sole portion 4012thickness is between about 1 mm and 2 mm.

Other than in the operating example, or unless otherwise expresslyspecified, all of the numerical ranges, amounts, values and percentagessuch as those for amounts of materials, moment of inertias, center ofgravity locations, loft, draft angles, various performance ratios, andothers in the aforementioned portions of the specification may be readas if prefaced by the word “about” even though the term “about” may notexpressly appear in the value, amount, or range. Accordingly, unlessindicated to the contrary, the numerical parameters set forth in theabove specification and attached claims are approximations that may varydepending upon the desired properties sought to be obtained by thepresent invention. At the very least, and not as an attempt to limit theapplication of the doctrine of equivalents to the scope of the claims,each numerical parameter should at least be construed in light of thenumber of reported significant digits and by applying ordinary roundingtechniques.

Notwithstanding that the numerical ranges and parameters setting forththe broad scope of the invention are approximations, the numericalvalues set forth in the specific examples are reported as precisely aspossible. Any numerical value, however, inherently contains certainerrors necessarily resulting from the standard deviation found in theirrespective testing measurements. Furthermore, when numerical ranges ofvarying scope are set forth herein, it is contemplated that anycombination of these values inclusive of the recited values may be used.

It should be understood, of course, that the foregoing relates toexemplary embodiments of the present invention and that modificationsmay be made without departing from the spirit and scope of the inventionas set forth in the following claims.

What is claimed is:
 1. A golf club comprised of a golf club head, ashaft having a shaft axis coupled to the golf club head at a first endof the shaft and a grip coupled to the shaft at a second end of theshaft, wherein the golf club head comprises: a frontal portion comprisedof metal comprising a striking face having a face center located at aforward portion of said golf club head; a non-metallic rear portionlocated aft of said striking face comprising a crown at an upper portionof said golf club and a sole on a bottom portion of said golf club; andwherein an x-axis is defined as a horizontal axis tangent to said facecenter with a positive x direction towards a heel of said golf clubhead, a y-axis is a vertical axis orthogonal to said x-axis with apositive y direction towards said crown of said golf club head, and az-axis being orthogonal to both said x-axis and said y-axis with apositive z direction extending forward, at least one first weightingmember located near a central portion of said golf club head in aheel-to-toe orientation, substantially in line with a vertical planecontaining the z-axis with said face center; wherein said golf club headhas a moment of inertia about said y-axis (MOI-Y) passing through acenter of gravity (CG) of said golf club head, said golf club head has amoment of inertia about said z-axis (MOI-Z) passing through said CG, andsaid golf club head has a moment of inertia about said x-axis (MOI-X)passing through said CG; wherein said golf club head has a MOI-Y toMOI-Z ratio of greater than about 1.5; and wherein said rear portionsole has the first weighting member secured thereto and the firstweighting member comprises an internal weight member, an external weightmember and a fastener that secures the internal weight member to theexternal weight member.
 2. The golf club of claim 1, wherein said golfclub head has a MOI-Y to MOI-Z ratio of greater than about 1.57.
 3. Thegolf club of claim 2, wherein said golf club head has a MOI-Y to MOI-Zratio of equal to or greater than about
 2. 4. The golf club of claim 1,wherein the golf club head has a CG-C, being a distance the CG is back,parallel to the z-axis, from the shaft axis, of between 14 mm to 21 mm.5. The golf club of claim 1, wherein said golf club head has a MOI-X toMOI-Z ratio of greater than about 1.10.
 6. The golf club of claim 5,wherein said golf club head has a MOI-X to MOI-Z ratio of greater thanabout 1.20.
 7. The golf club of claim 6, wherein said golf club head hasa MOI-X to MOI-Z ratio of greater than about 1.28.
 8. The golf club ofclaim 1 wherein said golf club head further comprises a crown returnlocated at a frontal portion of said crown made of metal, a sole returnlocated at a frontal portion of said sole made of metal, said solereturn comprising a second weighting member.
 9. The golf club of claim8, wherein said first weighting member and said second weighting memberare interchangeable to move a CG of the golf club head between a forwardposition and an aft position along a direction parallel to the z-axis.10. The golf club of claim 1, wherein said rear portion furthercomprises a sole plate member secured to an outer surface of the rearportion sole by coupling to the internal weight member and compressingthe rear portion sole therebetween.
 11. A golf club comprised of a golfclub head, a shaft having a shaft axis coupled to the golf club head ata first end of the shaft and a grip coupled to the shaft at a second endof the shaft, wherein the golf club head comprises: a frontal portioncomprised of metal comprising a striking face having a face centerlocated at a forward portion of said golf club head; a rear portioncomprising a thermoplastic material selected from the group consistingof polyetherimide, polyether ether ketone, polyphenylene sulfide,polysulfone, polyacryletherketone, polyetherketoneketone and polyvinylchloride and located aft of said striking face comprising a crown at anupper portion of said golf club and a sole on a bottom portion of saidgolf club; and wherein an x-axis is defined as a horizontal axis tangentto said face center with a positive x direction towards a heel of saidgolf club head, a y-axis is a vertical axis orthogonal to said x-axiswith a positive y direction towards said crown of said golf club head,and a z-axis being orthogonal to both said x-axis and said y-axis with apositive z direction extending forward, wherein said golf club head hasa moment of inertia about said y-axis (MOI-Y) passing through a centerof gravity (CG) of said golf club head, said golf club head has a momentof inertia about said z-axis (MOI-Z) passing through said CG, and saidgolf club head has a moment of inertia about said x-axis (MOI-X) passingthrough said CG; at least one first weighting member located on thesole, near a central portion of said golf club head in a heel-to-toeorientation, substantially in line with a vertical plane containing thez-axis with said face center; wherein said rear portion sole has thefirst weighting member secured thereto and the first weighting membercomprises an internal weight member and an external weight member and afastener that secures the internal weight member to the external weightmember and wherein the rear portion sole is compressed between theinternal weight member and a sole plate that is threaded to the internalweight member; and wherein said golf club head has a MOI-Y to MOI-Zratio of greater than about 1.5.
 12. The golf club of claim 11, whereinsaid rear portion is comprised of polyphenylene sulfide having acrystallinity of greater than 40%.
 13. The golf club of claim 11,wherein said rear portion is comprised of polyphenylene sulfide having acrystallinity between about 40% and 60%.
 14. The golf club of claim 11,wherein said rear portion is comprised of polyphenylene sulfide having acrystallinity of greater than 40% and glass filler in an amount ofbetween about 20% and 50%.
 15. A golf club comprised of a golf clubhead, a shaft having a shaft axis coupled to the golf club head at afirst end of the shaft and a grip coupled to the shaft at a second endof the shaft, wherein the golf club head comprises: a frontal portioncomprised of metal comprising a striking face having a face centerlocated at a forward portion of said golf club head; a rear portioncomprising a polyphenylene sulfide having a crystallinity of greaterthan 40% and located aft of said striking face comprising a crown at anupper portion of said golf club and a sole on a bottom portion of saidgolf club; wherein an x-axis is defined as a horizontal axis tangent tosaid face center with a positive x direction towards a heel of said golfclub head, a y-axis is a vertical axis orthogonal to said x-axis with apositive y direction towards said crown of said golf club head, and az-axis being orthogonal to both said x-axis and said y-axis with apositive z direction extending forward; wherein said golf club head hasa moment of inertia about said y-axis (MOI-Y) passing through a centerof gravity (CG) of said golf club head, said golf club head has a momentof inertia about said z-axis (MOI-Z) passing through said CG, and saidgolf club head has a moment of inertia about said x-axis (MOI-X) passingthrough said CG; and at least a first weighting member located on thesole, near a central portion of said golf club head in a heel-to-toeorientation, substantially in line with a vertical plane containing thez-axis with said face center.